1. Field of the Invention
This invention regards interrupting device for a contact pole in an electrical switching apparatus such as a circuit breaker, a contactor, a switch or a contactor-breaker, comprising a moving contact holder with a slide clamp-mounted on a mobile bridge supporting the mobile contacts. The invention also regards an electrical apparatus equipped with at least one such interrupting device.
2. Description of the Related Art
In a known electrical apparatus, the contact pole interrupting device comprises a moving contact holder, usually composed of a slide that moves along an axis between a rest position and a work position. The slide can be controlled by manual mechanisms, by magnetic and/or thermal tripping mechanisms in the event of an electrical fault. Its function is to mechanically displace a mobile bridge supporting the mobile contacts. This displacement causes the mobile contacts and the fixed contacts to separate, which corresponds to the rest position. In the work position, the mobile contacts are usually held against the fixed contacts by a contact pressure spring.
A switching apparatus contact pole is described in document DE19818058. It comprises a slide in which a mobile contact bridge is held in a opening in the slide by means of a contact spring. However, the slide does not have any special means to mount it on the mobile bridge without the contact spring.
Furthermore, in document U.S. Pat. No. 4,154,996 regarding a mechanical detector or limit switch, a mobile bridge is clamp-mounted in a piston (or slide) by a central opening in the mobile bridge. However, the contact pressure of the mobile bridge contacts on the fixed contacts is only transmitted by this clamp-mounting, which makes this solution unsuitable for a switching apparatus such as a circuit breaker, a contactor or a contactor-breaker, in which the electric currents circulating between the contacts are likely to be much greater than in a detector. Indeed, if there should be any wear play in the clamp-mounting at the end of a period of use, there is a risk of having a passage during the opening or closing of the contacts where the electrical contact will not exert any real pressure on the contacts, which would be redhibitory for the use described in this invention, on account of risks of fusion in particular.